From: Peter Szinek <peter@...>
Date: 2008-11-15T20:05:49+09:00
Subject: Re: how to call operator as function

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On 2008.11.15., at 11:56, Vladimir Fekete wrote:

> Hi *,
>
> could you help me please ? I'm trying to write a code where I could  
> have
> operators' functions as values of hash and executing them in way  
> like this
> (formal code):
>
> #=============================
> operators = { "+" => Fixnum.+,
>              "-" => Fixnum.-,
>              "++" => Myclass.++}
>
> op = "+"
>
> result = operators[op](left,right)  if left.class==Fixnum and  
> right.class==Fixnum
> #============================

++ is not supported by Ruby :)

I would do

1.send '+'.to_sym, 2

unless you want to use some esoteric operator mappings, you don't need  
the hash.
Fixnum.+ doesn't make that much sense because of Ruby's duck typing  
(and why would you want to restrict yourself to work with just certain  
objects?)

p.s.: dobre tu vidiet matfyzaka :-)

Cheers,
Peter
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